What is it?: Post-traumatic stress disorder, PTSD, is an anxiety disorder originally diagnosed among combat veterans, but can develop after exposure to any terrifying event or ordeal in which grave physical harm occurred or was threatened. Traumatic events that may trigger PTSD include violent personal assaults and natural or human-caused disasters or accidents, as well as military combat.

Signs and symptoms: People with PTSD have persistent frightening thoughts and memories of their ordeal and feel emotionally numb, especially with people they were once close to. They may experience sleep problems, feel detached or numb, or be easily startled.

Treatment: Effective treatments for post-traumatic stress disorder are available, and research is yielding new therapies that can help most people with PTSD and other anxiety disorders. Help is available at mental health clinics, both public and private. For more information about PTSD and about how and where to get help, go to www.nimh.nih.gov/healthinformation/